Among non-diabetic women, African-American women have significantly higher levels of apolipoprotein AI in HDL particles containing apoCIII (12.9 ± 2.8 mg/dL) than white women (10.9 ± 2.9 mg/dL) after adjustment for insulin sensitivity, despite lower insulin sensitivity and less visceral fat in African-American women, indicating race-specific differences in HDL subfraction composition.

In African-American women, liver cells produce more apoAI and less apoCIII than in white women, even when insulin resistance is similar. This happens because liver cells in African-American women have genetic differences that reduce the production of apoCIII and enhance the production of apoAI. The lower amount of apoCIII allows more apoAI to bind to HDL particles, increasing the concentration of apoAI in HDL particles that carry apoCIII. This occurs independently of fat around the organs or how well the body responds to insulin.